Button matrix



FIG. 1 is a top perspective view of a button matrix showing our new design, with the top surface of each button being opaque and the sides of each button being translucent;

FIG. 2 is a bottom perspective view thereof;

FIG. 3 is a top view thereof;

FIG. 4 is a bottom view thereof

FIG. 5 is a front elevation view thereof;

FIG. 6 is a rear elevation view thereof;

FIG. 7 is a left side elevation view thereof; and,

FIG. 8 is a right side elevation view thereof.

The parts shown in broken lines are for illustrative purposes only and form no part of the claimed design. 

CLAIM The ornamental design for a button matrix, as shown and described. 